The nitrogen removal performance and microbial community on mixotrophic denitrification process

Sulfur autotrophic denitrifiers and heterotrophic denitrifiers widely exist in aquatic ecosystem, however, the response of sulfide to the microbial community structure in mixotrophic denitrification ecosystem is unknown yet. In this study, the denitrification performance and microbial community were explored by changing the molar ratio of influent C/N/S. From the level of genus, the joint action of Thauera, Pacacoccus, Fusibacter Pseudoxanthomonas, Thiobacillus, Sulfurovum and Sulfurimonas brought about the efficient denitrification performance in the mixotrophic system. Thauera increased from from 0.97% to more than 13%, and the relative abundances of Thiobacillus and Sulfurimonas were about 4.14% and 3.89% separately after adding S2-. The re-sults of this study showed that the denitrification performance could be indeed intensified in the mixotrophic system, among which provided a theoretical basis for establishing an efficient biological nitrogen removal system.

Automated summary

By changing the molar ratio of influent C/N/S, this study explored the denitrification performance and microbial community in mixotrophic denitrification systems. The results showed that the joint action of several genera, including Thauera, Pacacoccus, Fusibacter Pseudoxanthomonas, Thiobacillus, Sulfurovum, and Sulfurimonas, contributed to efficient denitrification. The relative abundances of Thauera, Thiobacillus, and Sulfurimonas increased after the addition of S2-, indicating a potential mechanism for improving denitrification performance in mixotrophic systems.